This invention relates generally to mail handling capabilities utilized by interconnected computer systems. In particular, the present invention was implemented on a RISC System/6000 (RISC System/6000 is a trademark of IBM Corp.) workstation running the AIX (AIX is a trademark of IBM Corp.) operating system as described in detail by "IBM RISC System/6000 Technology", published 1990 by IBM Corp., hereby incorporated by reference. However, it should be noted that the present invention contemplates all multi-user systems interconnected into a network, e.g. Internet. That is, the present invention is in no way limited to a specific hardware platform, or software operating system, it is hardware and operating system independent.
The emergence of open system standards in a UNIX (UNIX is a registered trademark of AT&T) operating system environment has created a great need to provide an interface which will allow users of different communication protocols to communicate with one another. The open systems interconnect (OSI) standard utilizes a mail handling system known as X.400, while other mail handling systems utilize protocols such as simple mail transfer protocol (SMTP), and UNIX to UNIX copy protocol (UUCP). It is currently known to utilize an RFC-987 gateway which will convert an interpersonal message (IPM, which by definition is in the OSI, or X.400 mail format) from X.400 to communications protocols, such as Transmission Control Protocol (TCP), or the like. TCP/IP (Transmission Control Protocol/Internet Protocol) can be considered a family of communications protocols, of which SMTP is a communications (mail handling) program application protocol. When a message is received by an SMTP user via the RFC-987 gateway certain message header fields present in the X.400 mail may not be displayed to the SMTP mail recipient. Thus, with conventional mail handling systems a user does not have the capability to manage, both X.400 and RFC-822 mail from a single mail queue.
Therefore, it would be extremely desirable to have a mail handling system which provides a user the capability to manage both the X.400 and SMTP mail systems from a single mail queue, or local system. Further, a system that provides communications between users of different systems without the requirement that each sender and recipient each have identical mail handling capability would be a significant advantage over conventional mail handling systems.